Conventionally, a molding method of an injection molding machine disclosed in Patent Publication 1 suggested by the applicant of this application has been already known as a molding method of an injection molding machine by which molds consisting of a fixed mold and a movable mold clamped by a mold clamping apparatus at a predetermined mold clamping force are filled with injected resin by an injection apparatus at a predetermined injection pressure and an injection molding machine having a specific molding mode different from a general molding mode in particular.
This molding method has an objective of securing, even in the case of low-viscosity resin having a characteristic sensitively influenced by a temperature or a pressure for example, molded pieces having a high quality and homogeneity, achieving simpler molding conditions and easier setting, providing easier quality control, and reducing the molding cycle time, thereby improving the mass production and economy. Specifically, such a mold clamping apparatus is used that is a mold clamping apparatus providing the resin compression (natural compression) at least in accordance with the resin solidification in a mold, i.e., a direct pressure-type mold clamping apparatus to use a driving ram of a mold clamping cylinder to displace a movable mold, or a toggle-type mold clamping apparatus in which a tie bar installed between a fixed platen supporting a fixed platen and a pressure-receiving platen includes a movable platen supporting a movable mold in a slidable manner and a pressure-receiving platen and a movable platen have therebetween a toggle link mechanism and a driving mechanism section is used to drive the toggle link mechanism to clamp the mold in a non-lockup status. An injection pressure (molding injection pressure) and a mold clamping force (molding mold clamping force) that can provide a predetermined gap (mold gap) between a movable mold and a fixed mold during injection filling and a non-defective product are calculated and set in advance. During production, the molding mold clamping force is used to clamp the mold clamping apparatus and the molding injection pressure is set as a limit pressure. The injection apparatus is driven to inject and fill the resin into the mold. Thereafter, the passage of a predetermined cooling time is followed by the removal of a molded piece.